Greetings, grapple fans. Like The Wrestling every Saturday at four on ITV this tale of a heroin-addicted English boxer in a Bangkok prison is made up of strange rituals, hideous deprivation and unseemly physical contact. It's just like wrestling, except really violent.

There are men who like Thai boxing. There are men who like films about men in prison. It doesn't seem unreasonable that a Venn diagram of the two would see considerable overlap. Such groups though might be disappointed that rather than a tale of restorative violence triumphing over foreign otherness, this is an arthouse exercise in existential brutality, possibly inspired by Nicolas Winding Refn's Only God Forgives.

The film's philosophy is to suffer in the moment: there is no backstory, no explanation. Billy Moore (Cole) is presented as a figure only capable of inflicting or receiving pain. The kinetic camerawork mostly restricts itself to close-ups; it's rare to get an establishing shot of a location. There can be no peace or rest, no knowing where you stand.

It is almost a non-verbal experience (to westerners anyway) because most of the Thai dialogue passes without subtitle. Instead, this is a barrage of sound design where every slap and punch and thrust is played loud to overwhelming effect. Prison movies are normally associated with cells but in Thai jails there is no such luxury: everybody bunks down together on the floor and the place is so overcrowded that the bodies and flesh of the prisoners become intermingled, grafted together like a fluid human centipede.

You can't doubt the power of it but it's a languid intensity. The content is extreme but the film drifts through it, leaving the mind time to wander and be bothered by all the things left unexplained: how long is his sentence; why was he arrested; how much of the language does he understand; and do they really put ladyboys in men's prisons? Maybe those overflowing latrines begin to lose their shock value but in the second half, once he gets himself on the boxing team, the intensity dwindles.